Cloth-cutting machine.



1'. LlFSHITZ.

CLOTH CUTTING MACHINE.

APPLICATION FILED APR. 5. I9l8.

1,272,818. Patented July 16, 1918.

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m: Nonms PETERS m Puamuma, WASHINGWN. n. c.

NITE FFIQE.

IRVING LIFSHITZ, on NEW YORK, n. Y.

CLOTH-CUTTING- MACHINE.

Specification of Letters Patent.

Patented July 16, 1918.

' Application fi1edApri15, 1918. Serial No. 226,924.

To all whom it may concern Be it known that I, IRVING Lrrsnrrz, acitizen of Russia, and a resident of New York, in the county of New Yorkand State of New York, have invented certain new and usefulImprovementsin Cloth-Cutting Machines, of which the fOllOWiDg is aspecification.

This invention relates to cloth cutting machines of the reciprocatingblade type and resides primarily in the means for sharpening blades. Inmachines of this character the blade is ordinarily secured at, its upperend to the operating mechanism and is guided in the standard whichsupports said mechanism'from thebase. The lower end of the blade is freeand the range of movement is such that said lower end alternately entersand rises above a slotted throat plate substantially flush with thebase. The blade is not only sharpened along its front edge but is alsosharpened across at least a part of the lower end. Thus the knife duringthe downward movement cuts not only with the front edge but withthelower end.

The front edge of theblade may be readilysharpened tothe desired roughcutting or rippin edge without removing the blade from t e machine butthe cutting edge across the lower end must be sharpened to a razor edgeand it is this art which becomes dulled the most rapidly. an no machinewith which I am familiar can this be done. without the delay and troubleincidental to the removal of the blade from the machine.

The main object'of my. invention is to provide a sharpening mechanismparticularly desi ed to operate on this. lower end portion of the bladeand which may be attached to andpermanently carried by the machine. insuch a way as to not in any way interfere with the free normal use ofthe machine in the cutting of the'cloth. In its preferred embodiment Iemploy a sharpening mechanism including a pair of. rollers of appropriate material to act as grinders and position them in. thecomparatively small space beneath or within the base. As importantfeatures of my invention I so mount the grinders and their supportingand adjusting mechanism so that they may be readily removed from themachine at will and may be readily applied to any type of reciprocatingblade cloth cutting machine. Means are pros dd whereby th g i ders may ep a d.

and held in inoperative position or released for grinding operation in avery simple manner. The parts may be removed or replaced without the useof any special tools and without requiring the skill of experiencedmachinists.

' In the accompanying drawing I have illus trated one embodiment of myinvention although it will of course be evident that this is to beconsidered in an illustrative rather than in a limiting sense and thatvarious changes may be made within the scope of the nvention as definedin the appended claims.

In these drawings:

' Figure l is a top plan view of a portion of the base of a machine, thestandard and blade being shown in section.

Fig. 2 is a transverse section on the line 22 of Fig. l, on an enlargedscale.

Figs. 3 and a are vertical sections approximately on the lines 3 and 4:respectively of Fig. 1.

Fig. 5 is a top plan view of the grinders and their support removed fromthe base of the machine.

Figs. 6 and 7 are views of the opposite ends of the parts shown in Fig.5.

Fig. 8 is a side elevation of the parts shown in Fig. 5, the cover orthroat plate be ing shown in dotted lines in partly raised position.

Fig. 9 is a top plan View of the combined cover and throat plate.

Fig. 10 is a side elevation of the part shown in Fig. 9.

Fig; 11 shows one of the grinders and Fig. 12 shows one of the means forapplying adjustable resilient pressure to the grinders.

I have illustrated my invention in connection with parts of a commontype of cloth cutting machine. This includes a base 20, the sides andrear ortions of which curve downwardly toward the supporting surface.The body has a plurality of anti-friction rollers 21 for supporting thebase and the remainder of the machine carried thereby and forfacilitatin the forward movement of the machine during the cuttingoperation. Pivoted or hinged to the front edge of the body is theordinary apron 22, the front edge of which rests directly upon thesupporting surface and guides the base beneath the cloth to be cut.Threaded into an aper. ture in the base is the standard 23. T he portionof this standard above the level the This is also longitudinally.slotted; to formza;

guiding groove 24: for the knife 25. The

knife is mounted to reeiprocatewithin thisgroov e byoperating mechanismsupported at the upper end of the standard 23 but which it is notnecessary to illustrate. The lower end of the knife or blade is.sharpened not only along. its front cutting edge 26 but also along thefront portion of its bottomcutting edge'27' shown particularly in Fig4.. The blade when in lts downward limiting position occupiessubstantially the position shown in Fig. 4:, although when raised. itcomes some little distance above the upper surface of the base. Set inthe basein front of the standard and slotted to receive the knife iswhat is commonly known as a throat plate 28.v l he side and rear edgesof this are preferably slightly higher than the level of the uppersurface of the base as shown particularly in Fig. 2 so as-to properlyguide the cloth tothe knife preventing its catchingon the front edge ofthe standard. and aiding in reducingfriction. The parts so far describedare those commonly found in cloth cutting. machines of the reciprocatingblade type and the details thereof form no portion of my inventionexcept in-combination as hereinafter pointed out.

In carryingout my invention I provide a pair of rollers 30- of suchmaterial. that the rubbing engagement of the knife blade therewith willtend tosharpen the. latter. They may be of the same material as ordinaryoil stone usedfor sharpening or maybe of any other desired abrasive orsharpening material. These are mounted with their axes parallel to andspaced at equal distances upon opposite sides of the knife blade, and

within the space below the throat plate and above the level of thesupporting surface and upon which rests the rollers 21. The polishing orgrinding rollers 30 are resiliently pressed toward each other so thatwhen-the knife is raised the two rollers are in direct contact but.asthe knife reaches the lower end of its. movement the cutting edge 27enters between the two grinding. rollers and presses them apart therebyrubbing-over the surface of each and becoming sharpened.

y In practice, 1 preferably provide a housing creasing as shownparticularly in Figs. 5 to 8 inclusive- This is in the form of arectangular. metal box 31 having oppositely disposed outwardly.extendinglugs 32 adapt ed to receivebolts,xscrews,. or the like,'33. threadedintov the under. side of the base and holding the box or casing 31rigidly and firmly in place. The grinding rollers may be mounted in thebox in various different ways. but preferably each roller has reducedjournal end. portions 345. as shown particularly in Fig. 11 and theseenter in the bayonet slots 35 as shown particularly in Fig. 2. Therollers. after being dropped into the slots are moved toward each otherand thereby held" against any upward or downward movement. For pressingthe rollers together'l preferably provide suitable springs betweeireachvroller and the adjacent side of the housing. Such springs may bedesigned in various different ways but in order to readily adjust thetension; thereof I employ two coil springs 36 for each roller. each.springsetting against or being secured; to a curved bearing blade 3.7.for engagement witlrthe roller anda socket. stop 38 threaded in. anaperture in, the. side of the housing. By rotating these threaded stopsa greater or, lesser tension may be put on the springs and the rollersheld together with greater or lesserv pressure. Ihave not shown thesesprings. and. their supports in Fig. 2, they being purposely. omittedtherefrom to more clearly show the bayonet slots 35.

, The'topof therbox ouhou'singisopen and.

the housing isso. positioneddirectly beneath the throat. plate that thelatter may and preferably does serve as a coyer for the housing. f the;grinder r ll rs In. the construction. illustrated, the throat. plate. issecured. toenddireetly supported by the housing and merely fitswithin.the aperture in the base. 'The cover or throat plate 28 is shown; ashaving. two curved; or hooked projections 39' adjacent to one'end and. aslight groove. adjacentto the other. The. curve 0 hooked projection. 39may fit into apertures or depressions L0. in.v the endof. the housingnearestto. the standard and the; opposite end of, the housing may" haveaspring catch ll for engaging in the groove at the adjacent end-of the.throat, plate to resilientlyretainthe latter in position as shownparticularly in Fig. 8. It will of. coursebe understood that the end ofthe housing nearest to the standard is vertically slotted to receive theknife as is also. the bottom. wall of the housmg.

As it is not either necessary or desirable that the grinders. engage;with the ln ife blade. every time the lattercomes down. in cutting clothI provide. means for holding the. grlnders spaced apart in inoperativeposition whenever it is not; necessary to utilize their sharpeningfunctions. A very simple means. ofaccomplishingthis resultconiprises aset screw4c2 threaded through the-bottom of the housing and having apointed endfor engagement between the two grinder-rolL erfs'. "BylQWQling' this. set screw out of en gagement with the rollers they will.be pressed directl-ytogether by the springs and the; knife will besharpened duringthe'lower portion of each stroke. By giving'this. setscrew a. few turns the pointed end. W111 wedge between the grinderrollers and space them apart so that they will not engage with the knifeduring reciprocation of the latter and thegrinders will thus be held ininoperative position.

My improved device is very simple and inexpensive in construction and itis so designed that it may be applied to various different makes ofmachines with. little if any altention in the latter. The throat platesvary somewhat in size and shape in different makes of machines but it ismerely necessary to cut through the base an aperture of the proper sizeto receive the housing of my improved device and to provide a pair ofthreaded apertures for the attaching screws 33. The device is concealedfrom view and is beneath and protected from the cloth so that it doesnot in any way interfere with the free movement of the machine throughthe-cloth during the cutting operation. Any fine grit which may beproduced during the grinding operation falls through. and cannot come incontact with any part of the machine with which the cloth may laterengage, thus the cloth is protected against soiling. Any sparks whichmight result from the use of the device while the blade is in the clothwould either be retained within the housing or would fall through to thetable beneath the base and thus there is no liability of the sparksetting fire to the cloth. The grinders may be very easily removed andturned end for end when they become worn or the tenslon of the springsmay be easily changed, the only tool required being a screw driver andno special mechanical skill being needed. The condition of the grindersmay be easily inspected at any time by merely forcing the spring catch41 out of engagement with the throat plate 28 and lifting the latter.Any excess oil. used on the rollers or the bearing thereof, cannot dripon to the cloth as it is already beneath the level of the base overwhich the cloth passes. Various other advantages of my improved deviceand of obvious alterations thereof within the scope of the appendedclaims will be apparent to those skilled in the art.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

'1. A cloth cutting machine having a reciprocating knife presenting alongitudinally extending cutting side and a transversely extendingcutting end and a sharpening member in the path of movement of saidknife and with which said transversely extending cutting end may engageduring the final operation of its downward stroke.

2. A cloth cutting machine having a reciprocating knife havinglongitudinally and transversely extending cutting edges and a pair ofgrinder or sharpener members so positioned that the lower end of theknife may pass therebetween and engage with both during the lowerportion of its stroke to sharpen only said transversely extendingcutting edge.

3. A. cloth cutting machine having a reciprocating knife sharpenedtransversely of the lower end thereof and a pair of grinder or sharpenermembers resiliently pressed together and so'positioned that the lowerend of the knife may pass therebetween to separate them and engage withboth during the lower portion of its stroke to sharpen only saidtransverse cutting end.

4:. A cloth cutting machine having a base, a standard rising therefrom,a reciprocating knife, and a sharpener for the latter carried by thebase beneath the upper surface of the latter.

5. A cloth cutting machine including a base, a vertically movablereciprocating knife and a pair of grinder members carried by the basebeneath the upper surface of the latter for sharpening the lower end ofthe knife.

6. A cloth cutting machine having a base, a knife having a portionthereof movable therethrough and a pair of grinder memiers secured tothe under surface of the base for engaging with opposite sides of thedownwardly protruding part of the knife.

7. A cloth cutting machine including a base having a slot through whichthe cloth cutting member may extend and a pair of sharpener memberscarried by the base beneath the upper surface of the latter for engagingwith said cloth cutting member.

8. A cloth cutting machine having a base, and a pair of sharpeningrollers secured thereto beneath the upper surface thereof.

9. A cloth cutting machine including a base having a slot, a pair ofsharpening rollers beneath the base on opposite sides of the slot and aknife movable downwardly through said slot between said rollers.

10. In combination, a cloth cutting machine base, a housing secured tothe under surface thereof, and a pair of sharpening rollers within saidhousing.

11. In combination, a cloth cutting machine base, a housing secured tothe under surface thereof, and a pair of sharpening rollers within saidhousing, and resiliently pressed together.

12. In combination, a housing, a pair of sharpening rollers disposedtherein and re silently pressed together and means for securing saidhousing to the base of a cloth. cutting machine.

13. In combination, a housing having a pair of bayonet slots in each endthereof, a pair of rollers having their journals dis posed within saidslots and held against upward or downward movement, a pair of springsbetween each roller the adjacent side of the housing and means forattaching said housing to the base of the cloth cutting machine.

14:. In combination, a housing having a pair of bayonet slots in eachend thereof, a pair of rollers having their journals disposed withinsaid slots and held against upward or downward movement, a pair ofsprings between each roller and the adjacent side of the housing,separate. means for adjusting the tension of said springs, and means forattaching said housing to the base of the cloth cutting machine.

15. In combination, a housing, means for securing the same to the underside of a base of a cloth cutting machine, a pair of sharp ening memberswithin said housing, means for pressing said members toward each otherand an ad uStable member secured to one topics of this patent may beobtained for wall of the housing and adapted to enter be.- tween saidmembers for spreading them apart. I

16. In a cloth cutting machine a combination of a base, a sharpeningmember, a housing for the latter, and a combined housing cover andthroat plate.

17 In a cloth cutting machine a combina tion of a base having anaperture therethrough, a housing disposed within said base, a pair ofknife sharpening members within said housing, and a throat plate secured to said: housing and serving as a cover for the latter.

Signed at New York, in the county of New York, and State of New York,this 4th day of April A. D. 1918.

IRVING LIF SHITZ.

Washington, D. G.

